Electrical relay

ABSTRACT

A miniature relay, with an improved electromagnetic motor circuit and improved mechanical construction, for mounting on standard printed circuit boards. A balanced H-shaped armature pivots on the axis of its cross member for cooperation with either one or two stationary magnetic members or flux collectors. By utilizing one or both of the stationary magnetic members and/or the cross member of the armature in different combinations one, two or three energizing coils may be employed. The armature cross member or one or both stationary members may incorporate permanent magnets in different combinations with the energizing coils to provide polarized relays of different characteristics. Each stationary magnetic member provides two air gaps for exerting torque on the armature; the use of two stationary magnetic members or flux collectors provides four air gaps for exerting torque on the armature.

Sprando [451 Sept. 16, 1975 ELECTRICAL RELAY Anthony E. Sprando, 3115'N.W. Cornell Rd, Portland, Oreg. 97210 [22] Filed: Nov. 12, 1973 [21] Appl. No.: 414,919

[76] Inventor:

[52] US. Cl. 335/128; 335/125; 335/80;

335/234 [51] Int. Cl. HOIH 45/02 [58] Field of Search 335/229, 230, 234, 253, 335/254, 279, 128, 124, 125

[56] References Cited UNITED STATES PATENTS 2,741,728 4/1956 Distin 335/234 2,866,927 12/1958 Berget a]. 335/279 2,896,132 7/1959 Sauer 335/234 3,036,176 5/1962 Kenyon et a1... 335/125 3,048,678 8/1962 Reed et a1 335/80 X 3,097,328 7/1963 Sauer 335/279 X 3,147,349 9/1964 Welch et al.. 335/125 3,198,995 8/1965 Grebe 335/234 3,211,858 10/1965 Juptner 335/80 3,255,327 6/1966 Wood 335/124 3,273,087 9/1966 Huckabee 335/128 Primary Examiner-G. Harris Attorney, Agent, or Firm-Adrian J. LaRue ABSTRACT A miniature relay, with an improved electromagnetic motor circuit and improved mechanical construction, for mounting on standard printed circuit boards. A balanced H-shaped armature pivots on the axis of its cross member for cooperation with either one or two stationary magnetic members or flux collectors. By utilizing one or both of the stationary magnetic members and/or the cross member of the armature in different combinations one, two or three energizing coils may be employed. The armature cross member or one or both stationary members may incorporate permanent magnets in different combinations with the energizing coils to provide polarized relays of different characteristics. Each stationary magnetic member provides two air gaps for exerting torque on the armature; the use of two stationary magnetic members or flux collectors provides four air gaps for exerting torque on the armature.

12 Claims, 9 Drawing Figures BACKGROUND OF THE INVENTION This invention relates to improvements in electrical relays. l I

There is a need for miniaturized relays of'low profile which can be mounted compactly on standard printed circuit boards and which can be manufactured in quantity at low cost utilizing a minimum number of parts in different arrangements to provide a family of switching devices of different characteristics for different purposes. These objectives cannot be attained by merely scaling down conventional forms of construction.

. Objects of the invention are, therefore, to provide improvements to accomplish the foregoing objectives, to provide improved sensitivity, to provide a relay making more-efficient use of the space in which its parts are confined, to provide a relay having more air gaps in its magnetic circuit to develop increased torque in its armature, to provide a relay having a balanced H shaped armature, to provide a form of construction'which is quick and easy to assemble, to provide a relay having heatweldable thermoplastic frame parts, to provide an improved pin mounting for external circuit connections,'and to provide a relay capable of operation with very little power.

SUMMARY OF THE INVENTION Sensitivity isincreased by using a balanced H-shaped armature incombination with either one or two stationary magnetic members or flux collectors. A single stationary magnetic member interposes two air gaps in the magnetic circuit for developing torque in the armature. The use of a second stationary magnetic member establishes a second magnetic circuit which may be utilized to develop still greater torque in the armature as in a polarized sensitive relay.

By utilizing one or both stationary magnetic members and/or the cross member of the armature, one, two, or three energizing coils may be employed. The armature cross member or. one orboth of the stationary magnetic members may incorporate permanent magnets in different combinations with the energizing coils to provide polarized relays of different characteristics in a family of switching devices for different purposes.

The motor assembly is supported in thermoplastic frame parts which are conveniently heat weldable in assembly. Novel pin assemblies are provided to fit the sockets instandard printed circuit boards for high density stacking.

Additional objects and advantages will become apparent and the invention will be better understood with reference to the following description of certain preferred embodiments illustrated in the accompanying drawings. Various changes may be made in the details of construction and arrangement of parts and certain features may be used without others. All such modifications within the scope of the appended claims are included in the invention.

. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a sensitive relay embodying the invention, with parts broken away;

FIG. 2 is an exploded view of the relay in FIG. 1;

FIG. 3 is a view on the line 3-3 in FIG. 2; FIG. 4 is a cross sectional view of a sensitive relay on the line 44 in FIG. 1';

FIG. 5 is across sectional view of an ultrasensitive relay embodying the invention;

FIG. 6" is a similar view showing a three position sensitive relay;

FIG. 7 is a similar view showing a single coil magnetic latching relay;

FIG. 8 is a similar view showing a dual coil magnetic latching relay; and FIG. 9 is a perspective view of the armature in FIG.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in nos. 1, 2 and 3, all parts of the relay are mounted on a base or header 10 preferably made of a suitable thermoplastic'material such'as Delrin,

manufactured by E. I. du Pont de Nemours & Co. Two pin assemblies, as shown in FIG. 3, mount the relay in sockets in a printed circuit board and establish external circuit connections to the coils and switches in'the re- A pin assembly comprises the metal pins 11,12, 13, 14 and 15 of which the'pin '13 isno n-functional in this particular r'elay'. The pin assembly includes a bar of plastic material 16 which is molded around the pins to hold th'em'in proper relationship as a unit. Bar 16 is preferably made of a suitable thermoplastic such as Ryton, manufactured by Phillips "Petroleum Company, which will withstand soldering or welding temperatures. The plastic material of header 10 is molded around the bars 16 of the two pin assemblies, the Delrin having a higher shrink factor than the Ryton on cooling, causing the plastic in header 10 to form a compressive seal around each bar 16.

An elastic metal reed 20 carrying a reed contact 21 is soldered or welded on pin 11. A lower fixed contact 22 is soldered or welded on pin 15 and'an upper fixed contact 23 is soldered'or welded on pin 14. The ends of the relay solenoid coil are soldered or welded'to the pins 12 in the two pin assemblies. The soldering or welding temperatures to which the pins are" subjected are dissipated in the heat resistant plastic of bars "16 without softening or damagingthe plastic of header 10.

Opposite sides of header 10 are notched at24 to receive the lower ends of a pair of thermoplastic end frames 25 which are heat welded to the header. Each end frame 25 contains an armature bearing hole 26 and a pair of slots 27 and 28 on opposite sides of this bear- Ing.

A cylindrical iron flux collector core 29 carrying a solenoid coil 30 has rectangular pole pieces on its opposite ends mounted in slots 27 in the two end frames 25. The core 29 is retained in the slots 27 by a pair of thermoplastic inserts 31 which are heat welded to the frames 25. There being only one solenoid coil in this relay, the opposite sides of the frames 25 are stabilized by a thermoplastic armature backstop 'member 32 of the same shape as core 29, which is received in the slots 28 and heat welded to the frames 25.

The iron armature 35 is of H shape having an axial cross member 36 and two parallel radial arms 37 extending at right angles to cross member 36 at its opposite ends. The ends of cross member 36 are equipped with a pairof pivot pins 38 which rotate in the bearing holes 26 of the frames 25. The armature is symmetrical about the axis of pivot pins 38 whereby it is balanced on its center of mass and is not disturbed by external vibration or acceleration forces. The arms 37 carry a pair of torque arms 40 having glass beads 41 to engage and actuate reed contacts 21 on the two pin assemblies when coil 30 is energized.

The entire structure is sealed within a thermoplastic shell 45 which is heat welded to header10. After 'assembly, the air is evacuated from the shell through a small hole 39 and replaced by nitrogen, and the hole is heat sealed. The complete relay shown in FIG. 1 is 0.6 inch wide, 0.6 inch long and 0.4 inch high. However, no limitation is intended as to specific dimensions.

The relay shown in FIGS. 1 and 2 having the single energizing coil 30 is designated as a sensitive relay. With referenceto FIG. 4, resilient reed 20 normally biases reed contact 21 against upper stationary contact 23 and biases armature 35 counterclockwise away from the pole faces of core 29 and toward backstop member 32. When coil 30, isenergized, the two armature arms 37 are attracte d to the north and south pole faces on opposite ends of core 29, rotating the armature clockwise and causing torque arm 40 to shift reed contact 21 from stationary contact 23 to stationary contact 22.

The same switching event occurs at the other set of contacts associated with the second pin assembly shownin FIG. 2.whereby the entire switch mechanism coil 30is deenergized, the reeds 20 rotate the armature 35 counterclockwise and return both reed contacts 21 to the upper stationary contacts 23.

The ultrasensitive relay in FIG. is the same as the sensitive relay in FIG.,4 except that a second coil 50 is mounted on armature cross member 36. The polarity of coil 50 is reversed with respect to coil 30 so that a north armature arm 37 on one end of cross member 36 will be attracted to the south end of core 29 while the south armature arm 37 on the opposite end of cross member 36 will be attracted to the north end of core 29. The ultrasensitive relay in FIG. 5 thereby requires only half the. operating power of the sensitive relay in no.4.. I v

The modification in FIG. 6 is designated as a three position sensitive relay. This relay includes a second stationary flux collector core 59 and coil 60. The contact arrangement on the pin assemblies is reversed with reed a and reed contact 2182 extending to the left between lower stationary contact 22a and upper stationary contact 23a. Energization of coil 60 rotates the armature counterclockwise causing torque arm 40a to shift reed contact 21a from stationary contact 23a to contact 22a.

A pin assembly with a contact arrangement as shown in FIGS. 4 and 5 is out of the plane of the view in FIG. 6 for actuation by a torque arm 40 on the other armature arm 37, which is likewise out of the plane of the view. When coil 30 is energized, the armature is rotated clockwise to perform the switching functions illustrated in FIG. 5. This switch mechanism in FIG. 6 functions as two separate single-pole, double-throw switches. When both coils 30 and 60 are deenergized, the two reeds hold their respective reed contacts against the upper stationary contacts, causing the torque arms 40 and 40a to bias the armature to an intermediate position as shown. I

The relay in FIG. 7 is a bistable single coil magnetic latching relay. The cores 29 and 59 in FIG. 6 are replaced by a pair of permanent magnets 65 and 66 and the single coil 50 is mounted on the armature as in FIG.

S. The magnets 65 and 66 are reversed with respect to polarity so that the north end of one magnet lies opposite thesouth end of the other magnet. Torque arm 40a operates the reed contact 21a as in FIG. 6, while out of the plane of the view a second torque arm 40 on the other armature arm 37 operates a reversed reed contact corresponding to reed contact 21 in FIGS. 4 and 5. Thus, the switch in FIG. 7 constitutes a doublepole, double-throw switch.

When coil 50 energized in one polarity, the armature rotates counterclockwise causing torque arm 40a to move reed contact 21a. from upper stationary contact 23a to lower stationary contact 22a. The ene'rgization of the coilneeds to be only momentary. As soon as armature arms 37 engage the pole faces of magnet 66, the armature is retained in such position by magnetic attraction with the north armature arm 37 engaging the south pole face of magnet 66 and the south armature arm 37 engaging the north pole face of magnet 66. This magnetic attraction is superior to the spring force of reed 20a whereby the armature remains in its actuated position after coil 50 is deenergized and the armature remains in this position until coil 50 is energized with-reversed polarity. I I

When the direction of the current through coil 50 is reversed, the polarity of armature arms 37 is reversed so that the north armature arm 37 is engaging the north pole face of magnet 66 and the south armature arm 37 is engaging the southpole face of magnet 66. At the same time the'north armature arm 37 is attracted by the south pole face'of magnet 65 and the south armature arm 37 is attracted by the north pole face of magnet65. This produces clockwise rotation of the armature returning reed contact 21a to upper stationary contact 23a asshown and causing torque arm 40 to actuate the other reed contact downward. Again, the energization of coil 50 need be only momentary, the armature arms being held against the opposite polarity pole faces of magnet 65 by magnetic attraction after the coil has been deenergized.

The bistable-dual-coil latching relay in FIG. 8 performs the same functions as the relay in FIG. 7 but without the necessity for reversing the electrical connections; The switching function is that of a doublepole, double-throw switch as described in connection with FIG. 7.

As shown in FIG. 9, the axial cross member of the armature in FIG. 8 includes a permanent magnet 70. One of the soft iron radial arms 71 forms a north pole for the magnet and the other arm 71 forms its south pole. These parts are held inassembled relation by a pair of non-magnetic plates 72 which are welded at their ends to the arms 71.

The coils 30 and 60 are polarized in the same direc-' tion when energized, with the north pole faces of both cores 29 and 59 lying adjacent the arm 71 at the north end of magnet 70 and the south pole faces of both cores 29 and 59 lying adjacent the arm 71 at the south end of magnet 70.

In FIG. 8 both coils 30 and 60 are deenergized and the north and south armature arms 71 are magnetically latched to the opposite ends of soft iron core 59, holding reed contact 21a against lower stationary contact 22a and holding the other reed contact 21, which does not appear in FIG. 8, against upper stationary contact 23 in the second contact pin assembly shown in FIG. 2.

The armature is rotated clockwise by momentarily energizing coil 60,'causing the north pole of core 59 to repel the north'pole arm 71 and causing the south pole of core 59 to repel the south pole arm 71. At the same time, the opposite ends of north and south pole arms 71 are attracted to the opposite ends of soft iron core 29, magnetically latching arms 71 to core 29. This armature movement shifts reed contact 21a from contact 22a to contact 23a and shifts reed contact 21 from contact 23 to contact 22. The armature remains in this position after coil 60 is deenergized.

The armature is returned to FIG. 8 position by momentarily energizing coil 30, causing the north end of core 29 to repel the north pole arm 71 and causing the south end of core 29 to repel the south pole arm 71, while at the same time the opposite ends of arms 71 are attracted to core 59.

Still other modifications will suggest themselves to persons skilled in the art. For example, coils may be mounted on both cores 29 and 59 as shown in FIG. 6 and a third coil may be mounted on the axial armature cross member as shown in FIG. 7 to provide a three coil relay. With proper connections to the variouscoils, this arrangement provides a sensitive differential relay.

Having now described my invention, and in what manner the same may be used, what I claim as new and desire to protect by Letters Patent is:

1. An electromagnetic relay comprising:

a base plate of insulating material having pin means mounted therein at insulative spaced intervals; stationary contact means provided on first and second of said pin means; movable contact means mounted on third pin means and in engagement with said stationary contact means on said first pin means;

frame means provided by said base plate;

armature means of magnetizable material pivotally mounted to said frame means through an axial cross member thereof and. radial arm means extending outwardly from opposite sides of said axial cross member in one plane which is substantially parallel to said base plate and which moves about a pivot axis extending through said cross member;

electromagnetic means mounted on said frame means adjacent at least said radial arm means that extend from one side of said axial cross member;

and actuating means provided on said radial arm means, said actuating means engaging said movable contact means and moving said movable contact means from said first contact means to said second contact means upon energization of said electromagnetic means. I 2. An electromagnetic relay according to claim 1 wherein said armature means has an H configuration.

3. An electromagnetic relay according to claim 1 wherein other electromagnetic means is mounted on said cross member of said armature means.

4. An electromagnetic relay according to claim 1 wherein further electromagnetic means is mounted on said frame means adjacent said radial arm means that extends from the other of said cross member.

5. An electromagnetic relay according to claim 4 wherein permanent magnetic means are secured on said armature means.

6. An electromagnetic relay comprising:

base plate means of insulating material having stationary contact means provided thereon;

frame means provided by said base plate means;

armature means of magnetizable material having a cross member and arm means extending outwardly from opposite sides of said cross member;

means pivotally mounting said armature means to said frame means about an axis extending through said cross member with said arm means being disposed in a plane which is substantially parallel to said base means so that said arm means can move toward and away from said base means;

means disposed adjacent at least one of said arm means which will attract said one of said arm means thereto;

movable contact means for engagement with and disengagement with said stationary contact means; and

actuating means provided by said armature means and said movable contact means for moving said movable contact means into engagement with and disengagement with said stationary contact means upon attraction of said one of said arm means toward said means disposed adjacent said one of said arm means. 7. An electromagnetic relay according to claim 6 wherein said armature means has an H configuration.

8. An electromagnetic relay according to claim 6 wherein said attracting means comprises electromagnetic means.

9. An electromagnetic relay according to claim 6 .wherein other electromagnetic means is mounted on said cross member.

10. An electromagnetic relay according to claim 6 wherein further electromagnetic means is mounted on said frame means adjacent the other of said arm means.

11. An electromagnetic relay according to claim 9 wherein said attracting means comprise permanent magnet means.

12. An electromagnetic relay-according to claim 6 wherein said armature means comprises permanent magnetic means secured thereon. 

1. An electromagnetic relay comprising: a base plate of insulating material having pin means mounted therein at insulative spaced intervals; stationary contact means provided on first and second of said pin means; movable contact means mounted on third pin means and in engagement with said stationary contact means on said first pin means; frame means provided by said base plate; armature means of magnetizable material pivotally mounted to said frame means through an axial cross member thereof and radial arm means extending outwardly from opposite sides of said axial cross member in one plane which is substantially parallel to said base plate and which moves about a pivot axis extending through said cross member; electromagnetic means mounted on said frame means adjacent at least said radial arm means that extend from one side of said axial cross member; and actuating means provided on said radial arm means, said actuating means engaging said movable contact means and moving said movable contact means from said first contact means to said second contact means upon energization of said electromagnetic means.
 2. An electromagnetic relay according to claim 1 wherein said armature means has an H configuration.
 3. An electromagnetic relay according to claim 1 wherein other electromagnetic means is mounted on said cross member of said armature means.
 4. An electromagnetic relay according to claim 1 wherein further electromagnetic means is mounted on said frame means adjacent said radial arm means that extends from the other of said cross member.
 5. An electromagnetic relay according to claim 4 wherein permanent magnetic means are secured on said armature means.
 6. An electromagnetic relay comprising: base plate means of insulating material having stationary contact means provided thereon; frame means provided by said base plate means; armature means of magnetizable material having a cross member and arm means extending outwardly from opposite sides of said cross member; means pivotally mounting said armature means to said frame means about an axis extending through said cross member with said arm means being disposed in a plane which is substantially parallel to said base means so that said arm means can move toward and away from said base means; means disposed adjacent at least one of said arm means which will attract said one of said arm means thereto; movable contact means for engagement with and disengagement with said stationary contact means; and actuating means provided by said armature means and said movable contact means for moving said movable contact means into engagement with and disengagement with said stationary contact means upon attraction of said one of said arm means toward said means disposed adjacent said one of said arm means.
 7. An electromagnetic relay according to claim 6 wherein said armature means has an H configuration.
 8. An electromagnetic relay according to claim 6 wherein said attracting means comprises electromagnetic means.
 9. An electromagnetic relay according to claim 6 wherein other electromagnetic means is mounted on said cross member.
 10. An electromagnetic relay according to claim 6 wherein further electromagnetic means is mounted on said frame means adjacent the other of said arm means.
 11. An electromagnetic relay according to claim 9 wherein said attracting means comprise permanent magnet means.
 12. An electromagnetic relay according to claim 6 wherein said armature means comprises permanent magnEtic means secured thereon. 